.head{
    width: 85%;
    height: 120px;
    background-color: white;
    margin: 0 auto;
    border-bottom: 2px solid #e8e8e8;
}
.head1{
    width: 100%;
    height: 30px;
    background-color: #f5f5f5;
}
.ding{
    margin: 0 auto;
    width: 1200px;
    height: 30px;
}
.dingleft{
    float: left;
    width: 200px;
    height: 30px;
    /* text-decoration: none; */
    font-size: 12px;
}
.dingleft a{
    text-decoration: none;
    line-height: 30px;
    color: #999;
}
.dingleft a:hover{
    color: #3ab5e6;
}
.dingyou{
    float: right;
    height: 30px;
    font-size: 12px;

}
.dingyou a{
    text-decoration: none;
    line-height: 30px;
    color:#999;
}
.dingyou a:hover{
    color: #3ab5e6;
}
.a{
    width: 85%;
    height: 50px;
    margin-left: 7.5%;
    background-color: white;
}
.aa{
    float: left;
    font-size: 18px;
    line-height: 50px;
}
.ab{
    color: #999;
    text-align: right;
    float: right;
    line-height: 50px;
}
.b{
    width: 85%;
    height: 500px;
    background-color: white;
    margin: 0 auto;
    overflow:auto;
}
.ba{
    text-align: center;
    font-size: 60px;
    padding-top: 200px;
}
.bb{
    text-align: center;
    font-size: 18px;
}
button {
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 50px;
    position: relative;
    padding: 0 20px;
    font-size: 18px;
    text-transform: uppercase;
    border: 0;
    box-shadow: hsl(210deg 87% 36%) 0px 7px 0px 0px;
    background-color: hsl(210deg 100% 44%);
    border-radius: 12px;
    overflow: hidden;
    transition: 31ms cubic-bezier(.5, .7, .4, 1);
}

button:before {
    content: attr(alt);
    display: flex;
    align-items: center;
    justify-content: center;
    position: absolute;
    inset: 0;
    font-size: 15px;
    font-weight: bold;
    color: white;
    letter-spacing: 4px;
    opacity: 1;
}

button:active {
    box-shadow: none;
    transform: translateY(7px);
    transition: 35ms cubic-bezier(.5, .7, .4, 1);
}

button:hover:before {
    transition: all .0s;
    transform: translateY(100%);
    opacity: 0;
}

button i {
    color: white;
    font-size: 15px;
    font-weight: bold;
    letter-spacing: 4px;
    font-style: normal;
    transition: all 2s ease;
    transform: translateY(-20px);
    opacity: 0;
}

button:hover i {
    transition: all .2s ease;
    transform: translateY(0px);
    opacity: 1;
}

button:hover i:nth-child(1) {
    transition-delay: 0.045s;
}

button:hover i:nth-child(2) {
    transition-delay: calc(0.045s * 3);
}

button:hover i:nth-child(3) {
    transition-delay: calc(0.045s * 4);
}

button:hover i:nth-child(4) {
    transition-delay: calc(0.045s * 5);
}

button:hover i:nth-child(6) {
    transition-delay: calc(0.045s * 6);
}

button:hover i:nth-child(7) {
    transition-delay: calc(0.045s * 7);
}

button:hover i:nth-child(8) {
    transition-delay: calc(0.045s * 8);
}

button:hover i:nth-child(9) {
    transition-delay: calc(0.045s * 9);
}

button:hover i:nth-child(10) {
    transition-delay: calc(0.045s * 10);
}
